2021. Setting up Java Development Environment on Ubuntu
JDK, Tomcat, and Eclipse

Install JDK, Apache Tomcat and Eclipse on Ubuntu.

We will use the following free softwares/tools.

JDK - Java SE Development Kit, a free integrated development kit used to build, test, and deploy Java applications.
Apache Tomcat - An open source web server.
Eclipse - One of the most widely used Java IDEs.

1. Installing JDK in Ubuntu

1.1 Downloading Oracle JDK

In Ubuntu VM, download the latest version of JDK from http://www.oracle.com/technetwork/java/javase/downloads/index.html. Select JDK, in the next page, accept the license and choose ‘jdk-8u144-linux-x64.tar.gz’ to download.

1.2 Installing JDK

There is no installer, have to configure JKD manually. Unzip the package and move JDK files to /usr/local/java/

$ sudo cp -r jdk-8u144-linux-x64.tar.gz /usr/local/java/
$ cd /usr/local/java
$ tar xvzf jdk-8u144-linux-x64.tar.gz

Finally, JDK is installed to /usr/local/java/jdk1.8.0_144/.

1.3 Setting up Environment Variables for Java

Create new environment variable of JAVA_HOME and add it to PATH.

$ sudo nano /etc/profile

Add the following contents to the end.

JAVA_HOME=/usr/local/java/jdk1.8.0_144
PATH=$PATH:$JAVA_HOME/bin
export JAVA_HOME
export PATH

1.4 Informing Ubuntu where Java JDK is located.

$ sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.8.0_144/bin/java" 1
$ sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.8.0_144/bin/javac" 1
$ sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.8.0_144/bin/javaws" 1

1.5 Checking Java Version

$ java -version

You should be able to see the java information like below.

java version "1.8.0_144"
Java(TM) SE Runtime Environment (build 1.8.0_144-b01)
Java HotSpot(TM) 64-Bit Server VM (build 25.144-b01, mixed mode)

2. Setting up Apache Tomcat

2.1 Downloading Tomcat

In Ubuntu VM, download the latest version of Tomcat from https://tomcat.apache.org/.

2.2 Installing Tomcat

There is no installer, have to configure Tomcat manually. Unzip the tar file, copy to /opt/tomcat.

$ tar xvzf apache-tomcat-8.5.23.tar.gz
$ sudo mv apache-tomcat-8.5.23 /opt/tomcat

2.3 Setting up Environment Variables for Tomcat

1) Open .bashrc for editing

$ nano ~/.bashrc

2) Set CATALINA_HOME environment variable pointing to the installation locations. Add this information to the end of the file:

$ export CATALINA_HOME=/opt/tomcat

3) Simply save and exit .bashrc, then make the changes effective by running the following command:

$ . ~/.bashrc

2.4 Adding User for Tomcat

$ nano $CATALINA_HOME/conf/tomcat-users.xml

Add role and admin user to this file.

<tomcat-users>
<!--
  <role rolename="tomcat"/>
  <role rolename="role1"/>
  <user username="tomcat" password="tomcat" roles="tomcat"/>
  <user username="both" password="tomcat" roles="tomcat,role1"/>
  <user username="role1" password="tomcat" roles="role1"/>
-->

    <role rolename="manager-gui"/>
    <user username="admin" password="admin" roles="manager-gui"/>

</tomcat-users>

2.5 Starting Tomcat

$ $CATALINA_HOME/bin/startup.sh

Verify that Tomcat is working by visiting http://localhost:8080. tomcat
Tomcat can be stopped by executing the following command:

$ $CATALINA_HOME/bin/shutdown.sh

3. Installing Eclipse

3.1 Downloading Eclipse

Download the latest version of Eclipse from https://www.eclipse.org/downloads/. After downloading is finished, unzip the tar file.

$ tar xvzf eclipse-inst-linux64.tar.gz

3.2 Installing Eclipse

Go to the uncompressed folder ‘eclipse-installer’, double click the installation file ‘eclipse-inst’. installeclipse
In the wizard, select ‘Eclipse IDE for Java EE Developers’. jee
Leave the installation folder unchanged, click ‘INSTALL’ button. location
Installation should start and wait until it is finished. If you see ‘read-only’ error, run the following command, and try to install again.

$ sudo chown -R $USER /opt/  // grant all access of rights for folder /opt/ to current user.

3.3 Starting Eclipse

Launch Eclipse through UI or run command as follows.

$ cd /home/johnny/eclipse/jee-oxygen/eclipse/
$ ./eclipse

Set workspace. eclipse_workspace
Close the welcome page, you will get Eclipse ready for use. eclipse_launched

In addition, if your eclipse icon is missing after you launch it, copy icon.xpm to /usr/share/pixmaps/, and rename it to eclipse.xpm.

$ cp /home/johnny/eclipse/jee-oxygen/eclipse/icon.xpm /usr/share/pixmaps/eclipse.xpm

2021. Setting up Java Development Environment on UbuntuJDK, Tomcat, and Eclipse